I loved it and I felt like the colors and atmosphere were downright gorgeous! I'm really glad they used a lot of practical effects and makeup instead of slathering everything in CGI like a lot of other studios would have easily done. This film's visuals is going to age well with time.
I recently copped the deluxe Blu Ray copy and after watching the behind the scenes special features it was insane how much background mythos James Gunn created. He had just mountains of stuff on all the designs, a detailed story for Drax's tattoos, background information on all the races on the film and just a bunch of intricate details about settings that people won't even get to see or know about. It's great because he will have some great source material for the future sequels but I hope he comes out with a book detailing it all or something. They weren't lying when they said it was like the new star wars because James Gunn created a massive world that you can really obsess about on some crazy Star Trek fanboy type of level.
I'm even thinking about getting a playstation 3D display off of ebay JUST so I can
watch the 3D blu ray version of this film on my ps triple. It was amazing in 3D when I saw it in theaters so I hope the home experience rivals that. I just wished I saw it on IMAX tbh. It would have been a GOAT experience.